The present invention relates to an integrated apparatus for producing warm water.
"Integrated" apparatuses for producing warm water, for example for heating systems and/or for sanitary uses, i.e. apparatuses employing a heat pump combined with one or more auxiliary heat sources, such as a gas-powered, gas oil-powered electric-resistor burner and/or solar-energy means, i.e. solar-panels or taking advantage of the greenhouse effect, have already been proposed in the past. In general, such integrated apparatuses can be quite efficient, which results in considerable savings in terms of heat originating from non-renewable energy sources. However, problems sometimes occur in operating integrated apparatuses and in exploiting at best all heat made available by the heat sources. Thus, for example, the refrigerating gas flowing through the refrigerating circuit of a heat pump tends to become overheated in the regions close to the gas- or gas oil-powered burner, and any overheating can significantly alter its physical and chemical characteristics and therefore the behavior of the refrigerating fluid in the circuit, especially in cases when the supply of electric power to its driving apparatus is accidentally interrupted.
Furthermore, as is known, an air/water heat pump is best effective at temperatures of a few degrees above 0.degree. C. As a matter of fact, when the temperature drops below zero the evaporator of the heat pump becomes covered with a layer of ice which is difficult to eliminate unless additional thermal energy is supplied to it.